Economical importance of bryophytes

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ECOLOGICAL IMPORTANCE OF BRYOPHYTES Mosses and Bryophytes are the first organiasms to colonise rocks. They colonise rock by acidic secretion. This acidic secretion is due to the death of mosses. When the rock is decomposed it helps in soil formation. Therefore New soils are formed. The soil act as binders.  It prevent soil erosion. The water retention capacity of the soil is high ie, water holding capacity of the soil is high.  This reduces surface water run-off which prevent soil erosion. Bryophyte helps in the recycling of nutrients. ECONOMICAL IMPORTANCE OF BRYOPHYTES. 1) SPHAGNUM Sphagnum has high absorptive power with antiseptic property. This can be used to replace cotton in bandages. 2) MERCHANTIA   Mercahntia cures pulmonary tuberculosisand affliction (pain) in liver. Antibiotic substances are also extracted from bryophytes. it also acts as antiseptic, and as preservative POLYTRICHUM Polytrichum dissolove stone in kidney and in gall bladder. 3) IN RESEARCH It is used in the fie
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what isHaplodiplontic life cycle ( biphasic) .

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Haplodiplontic life cycle

   The life cycle of an organisms which both gametophytic and sporophytic generation found for long time is called haplodiplontic life cycle.
   It's further divided into two types ie., 
 a. Biphasic
  b. Triphasic

 Biphasic life cycle ( both phase found) 
    The life cycle in which , there is a succession of two generation ie gametophytic generation and generation. It's of following types.

I. Isomorphic type
     In this type of life cycle,there is an altercation of generation in which both phase are externally similar, and can be distinguished by counting the chromosome number.
         the haploid plant produce haploid gametes  which are fused to form diploid zygote which directly terminate into a diploid plant.the diploid sex organs of the diploid plant produce diploid gametes ie spore which undergoes reductional division to produce haploid gametes or haploid zoospores which directly grow into haploid plant .the haploid plant produce haploid gametes ie male and female gametes which are similar in morphology and they fused to form diploid zygote. In this way the cycle is completed.

        Found in green algae ( Ulva , Cladophora) , brown algae ( Ectocarpous etc) .

ii.Heteromorphic type

     In this type of life cycle both the haploid and diploid plant body are externally similar in morphology , and they alternate to each other.
        The diploid plant produces haploid gametes ( of morphologically disimilar male and female gametes express as a difference in cell size and degree of branching.)  by reduction division and they germinate into haploid plant directly, the haploid plant produce haploid gametes which are fused to form diploid zygote which directly germinate into diploid plant.here mostly the sporophyte is large and gametophyte is small.p

             Ex., Mainly almost in all brown algae ie Dictyota ,Laminaria etc. But in genera like Cutleria and Urospora  the haploid plant is large and diploid plant is small.

All the best....

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